Not to mention that if they deign to port it to Steam there will be the inevitable need for a screen filter removal mod. 
More like it will be a lazy garbage mobile to PC port that not only looks terrible, but runs at the wrong framerate, only supports an asinine aspect ratio, and uses a mobile phone UI.
Seriously, you'd be just better off playing the mobile version in Bluestacks.
The only AAA company that does a more incompetent job at PC ports of Japanese games than Square Enix is Tecmo Koei. Bandai Namco is a up there too with how inconsistent they are.